io THE FACTORS OF THE MIND

cedure as a whole has ever been attempted. In a later
chapter1 I shall show that the results of any one method
bear direct and simple relations to those of any other ; so that
all the methods stand or fall together. The detailed differ-
ences between the various devices hitherto proposed have
been described and discussed with great impartiality and
clearness by Prof. Godfrey Thomson in a recent publica-
tion.2 Hence their special features need not detain us here.
Prof. Thomson's book, however, has brought the chief
issues to a head. Though he has never condemned the
general method in itself, he has always been one of the
most vigorous critics of the conclusions popularly drawn,
The aims of factor-analysis, as usually stated, he readily
accepts : its objects, he says, are twofold—" to arrive at an
analysis of mind based on the mathematical treatment of
experimental data obtained from tests of intelligence and
of other qualities, and to improve vocational and scholastic
advice and prediction by making use of this analysis in
individual cases/' 3 But whether the mental factors thus
arrived at will be so few or so simple as is commonly main-
tained, he very much doubts. From the first he has
opposed the familiar theory that there is a single central
factor pervading and dominating all the activities of the
mind — f Spearman's g ' or ' general intelligence/ as it is
variously termed ; and in his more recent discussions he goes
farther still, and rejects the whole notion that the human
mind may be constructed out of a small number of funda-
mental capacities or traits. " Far from being divided up
into unitary factors, the mind is a rich, comparatively
undifferentiated complex of innumerable influences—on
the physiological side an intricate network of possibilities of
intercommunication." The mathematical peculiarities ex-
hibited by our correlation tables are attributable, so he
believes, not to psychological laws, but to statistical laws :
they are at bottom simply the result of sampling the in-
numerable factorial elements of which the mind is

1 See below, pp. 365 f.

2 The Factorial Analysis of Human Ability^ 1939* Cf. also Appendix 1
for illustrations of the chief methods.

3 Loc. dt., p. 3.